Both countries are full members of the European Union, NATO, Bucharest Nine, Three Seas Initiative, OSCE, Council of Europe and World Trade Organization.

Bulgarians and Poles fought together as part of a larger European coalition at the Battle of Nicopolis in 1396 in an attempt to stop the Ottoman invasion and conquest of Bulgaria.

Bulgarian insurgents of Fruzhin fought alongside Poles in hope of restoring independence, however, the battle ended in the defeat of the coalition army and the death of the Polish king.

[9] One of the escape routes of Poles who fled to Hungary after the German-Soviet invasion of Poland, which started World War II, to Polish-allied France, where the Polish Army was reconstituted to continue the fight against Germany, led through Bulgaria.

[10] Bulgaria confidentially authorized the evacuation of Poles through its territory, after difficulties began to arise in escaping through Yugoslavia and Greece, due to those countries' fear of Germany.

For the first time in 13 years, on 18 April 2016, the Polish president, Andrzej Duda, was on a state visit to Sofia to meet his counterpart Rossen Plevneliev and Bulgaria's prime minister Boyko Borisov.

In a joint press conference Presidents Plevneliev and Duda called for Russia to give up its "aggressive actions" and "come back" to international order and stood by the sovereignty and territorial integrity of Ukraine.

[21] Prime minister Borisov noted that Poland is a "very important country" for Bulgaria and Sofia values the development of bilateral relations in the context of the EU and NATO.

[22] President Duda said that his visit in Sofia is a "realization of the ABC format" – Adriatic, Baltic, Black Sea (in Polish – Adriatyk, Bałtyk, Czarne [Morze]) – a project to expand the transport and energy infrastructure in this large region.

[27] Major Bulgarian cities like the capital Sofia and Varna on the Black Sea coast have purchased Polish-made trams and buses for their public transport systems.

[citation needed] In October 2015, Bulgaria signed a contract with two Polish companies to carry out repair works on six engines for the country's Mig-29 fighter jets.

[31] In March 2016, at an international conference in Warsaw government representatives from Lithuania, Poland, Romania, Slovakia, Turkey, Hungary and Ukraine signed a declaration on promoting the construction of the new transport route named Via Carpathia.